ASSESSING URBAN FOREST CANOPY COVER IN GREAT PLAIN CONSERVATION AREA (DÜZCE CITY, TURKEY) BETWEEN 1984 AND 2015

Urban trees and forests are essential components of the urban environment. They can provide numerous ecosystem services and goods, including but not limited to recreational opportunities and aesthetic values, removal of air pollutants, improving air and water quality, providing shade and cooling effect, reducing energy use, and storage of atmospheric CO2. However, urban trees and forests have been in danger of being lost by dense housing resulting from population growth in the cities since the 1950s, leading to increased local temperature, pollution level, and flooding risk. Thus, determining the status of urban trees and forests is necessary for comprehensive understanding and quantifying the ecosystem services and goods. Tree canopy cover is a relatively quick, easy to obtain, and cost-effective urban forestry metric broadly used to estimate ecosystem services and goods of the urban forest. This study aimed to determine urban forest canopy cover areas and monitor the changes between 1984–2015 for the Great Plain Conservation area (GPCA) that has been declared as a conservation Area (GPCA) in 2017, located on the border of Düzce City (Western Black Sea Region of Turkey). Although GPCA is a conservation area for agricultural purposes, it consists of the city center with 250,000 population and most settlement areas. A random point sampling approach, the most common sampling approach, was applied to estimate urban tree canopy cover and their changes over time from historical aerial imageries. Tree canopy cover ranged from 16.0% to 27.4% within the study period. The changes in urban canopy cover between 1984–1999 and 1999–2015 were statistically significant, while there was no statistical difference compared to the changes in tree canopy cover between 1984–2015. The result of the study suggested that an accurate estimate of urban tree canopy cover and monitoring long-term canopy cover changes are essential to determine the current situation and the trends for the future. It will help city planners and policymakers in decision-making processes for the future of urban areas.

Remotely Sensed Tree Characterization in Urban Areas: A Review

Urban trees and forests provide multiple ecosystem services (ES), including temperature regulation, carbon sequestration, and biodiversity. Interest in ES has increased amongst policymakers, scientists, and citizens given the extent and growth of urbanized areas globally. However, the methods and techniques used to properly assess biodiversity and ES provided by vegetation in urban environments, at large scales, are insufficient. Individual tree identification and characterization are some of the most critical issues used to evaluate urban biodiversity and ES, given the complex spatial distribution of vegetation in urban areas and the scarcity or complete lack of systematized urban tree inventories at large scales, e.g., at the regional or national levels. This often limits our knowledge on their contributions toward shaping biodiversity and ES in urban areas worldwide. This paper provides an analysis of the state-of-the-art studies and was carried out based on a systematic review of 48 scientific papers published during the last five years (2016–2020), related to urban tree and greenery characterization, remote sensing techniques for tree identification, processing methods, and data analysis to classify and segment trees. In particular, we focused on urban tree and forest characterization using remotely sensed data and identified frontiers in scientific knowledge that may be expanded with new developments in the near future. We found advantages and limitations associated with both data sources and processing methods, from which we drew recommendations for further development of tree inventory and characterization in urban forestry science. Finally, a critical discussion on the current state of the methods, as well as on the challenges and directions for future research, is presented.

Effects of Composts Made from Broiler Chicken Residues and Blended with Biochar on the Minerals and Phenolic Compounds in Parsley (Petroselinum crispum Mill.)

Soil amendments, such as composts and biochar, are currently widely used as substrates in container gardening. Although different types of wastes have been used in composting, formulating growing mediums for specific plants using different materials is necessary. In the present study, organic substrates comprising mixtures of (a) broiler chicken wastes composted with sugar bagasse, sawdust, urban tree, napier grass, or cotton residues, and (b) five different proportions of biochar (0%, 15%, 30%, 45%, and 60%) were used to produce mineral and flavonoid-rich parsley plants. The sawdust-based substrate led to the highest yields (27.86 g pot−1 on average), regardless of the amount of biochar added; however, this substrate resulted in plants with no appreciable antioxidant activities. Plants grown using the tree-based substrate had moderate yields (16.95 g pot−1), and the highest phenolic levels (e.g., 7.93 mg GAE g−1) and antioxidant activities (DPPH scavenging activity over 11.17 g TE g−1). Such activities were better described by the presence of apigenin-7-apiosylglucoside and diosmetin-apiosylglucoside. Moderate yields were also obtained with the cotton-based substrate; however, such yields were only obtained at biochar proportions greater than 30%; this substrate led to the highest K contents (47.19 g kg−1). The lowest yields (3.20 g pot−1) and N (20.96 g kg−1), P (1.33 g kg−1), K (33.26 g kg−1), and flavonoid (13.63 mg CE g−1) contents were obtained with the napier-based substrate. However, this substrate led to the production of parsley plants with the highest levels of anthocyanins (0.40 mg CGE g−1), which may have accumulated as stress sensors and defense components. The bagasse-based substrate also led to high yields and appreciable flavonoid contents with 60% biochar. In most cases, no linear relationship was found between the biochar amount and the chemical parameters evaluated. Overall, the substrates formulated using urban tree residues had higher suitability for parsley development than those formulated using sugar bagasse, sawdust, napier grass, or cotton residues.